Low birthweight has been a longstanding issue in Bradford, and a hard one to tackle; the ethnic-specific trends described in this study can help policy makers and practitioners focus prevention efforts appropriately.
Low birthweight has been strongly associated with poor health outcomes in childhood and adulthood. Understanding how ethnicity and socio-economic factors drive birthweight outcomes is critical. Multivariate regression models analysed the prevalence of low birthweight in certain ethnic groups alongside maternal and socio-economic variables. Our research offers a unique insight into the temporal birthweight changes in a multi-ethnic, materially deprived community over a time period in which austerity measures took effect.
Data and methods
Using data on 4829 births obtained by Born in Bradford (2007-2011) and Born in Bradford Better Start (2016-2020), this study analysed the prevalence of low birthweight in certain ethnic groups alongside maternal and socio-economic variables. We employed multivariate regression models to longitudinally analyse birth data and maternal, behavioural and socio-economic variables by ethnic group.
Born in Bradford’s cross-sectional studies enabled our research to identify low birthweight as an issue for ethnicities in Bradford, whether rising or constant.
Average birthweight of Pakistani heritage and other South Asian heritage children is significantly lower than the England average. From 2007 to 2020 Pakistani heritage infants had consistently elevated low birthweight, fluctuating between 9.7% (8.3%-11.3%) and 7.7% (6.5%-9.2%), while Other South Asian heritage increases from 11.0% (7.4%-16.1%) to 14.1% (10.0%-19.5%).
Low birthweight in the White British population nearly doubled over the austerity period, from 5.0% (3.3%-7.6%) to 9.3% (6.4%-13.2%).
Results from the logistic regression models that investigated trends in low birthweight, by treating the data as a single longitudinal dataset, are presented in models A and B below; these models allowed for different trajectories of change in low birthweight over time for each ethnic group.
Considering the results, community can be speculated as a protective factor from the effects of austerity; low birthweight worsened for more socially-isolated individuals as governmental support available diminished, particularly affecting the White British population.
Although at a concerning rate, low birthweight for Pakistani heritage and other South Asian heritage infants remained fairly steady, potentially due to the support available within minority ethnic communities, which may have depended on more than governmental programmes.
Value of the research
Comparing two rich longitudinal datasets is a unique strength of the Born in Bradford studies. Looking at a multi-ethnic, materially deprived community, this study has shown that low birthweight is an issue in Bradford, worsening across certain ethnic groups.
Targeting policies and resources by considering ethnicity is necessary to combat low birthweight. Considering ethnicity in these efforts is a generally applicable strategy that enables place-specific localised efforts.
- Birthweight is a concern in the materially deprived Better Start area of Bradford, worsening for some groups over the austerity period
- Low birthweight is a consistent issue for Pakistani heritage and other South Asian heritage infants
- Low birthweight rate almost doubled for the White British population
- Community may be a protective factor explaining changes in birthweight over time
Epidemiological Statistical Methods
Alexandra Dalton, Data Scientist Intern (LIDA)
Dr Brian Kelly (Bradford Institute for Health Research)
Born in Bradford; Bradford Institute for Health Research
Bradford Institute for Health Research (BIHR)